Blood pressure

Blood pressure is force of blood against the walls of blood vessels. Blood pressure is usually measured while you are seated with your arm resting on a table. Your arm should be slightly bent so that it is at the same level as your heart.

Blood pressure is expressed by two numbers. The higher number represents systolic blood pressure, the pressure in the arteries when the heart muscle is contracting and pumping blood into the arteries.

Optimal systolic blood pressure is 120 millimeters of mercury (mm Hg) or less.
The second value is diastolic blood pressure, the artery pressure when the heart relaxes between beats. Optimal diastolic blood pressure is 80 mm Hg or less.

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Some people have a blood pressure level that is lower than normal. Only one of the numbers has to be lower than it should be to count as low blood pressure. There is no specific reason for having low blood pressure. In some cases, certain medicines can cause low blood pressure.

Hypertension or high blood pressure is the chronic elevation of blood pressure levels. High blood pressure is a major health problem affecting approximately 30% of adults in western societies. Because it has few, if any, signs and symptoms, it is thus called the “silent killer”. There are usually no signs or symptoms of high blood pressure until it gets dangerously high. 

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